Score Higher on Verified INF-306 | HTML5 Application Development Exam Questions with Answers

pattern ? Provides a way to set a regular expression that the value must match

placeholder ? Provides a way to set default text that displays until focus is placed in an element

required ? Provides a way to set form elements as mandatory

multiple ? Provides a way to allow more than one file or email address in a single input

The correct matches are based on standard HTML5 form validation and input-attribute behavior. The pattern attribute defines a regular expression that the input value must satisfy before the form can be submitted successfully. It is commonly used for structured values such as phone numbers, codes, postal formats, or custom identifiers. The placeholder attribute supplies short hint text inside an input field, helping the user understand the expected value before entering data. The required attribute makes a form control mandatory; if the field is empty, constraint validation prevents successful submission. The multiple attribute allows a single input to accept more than one value, specifically for controls such as input type= " file " and input type= " email " , where users may upload multiple files or enter multiple email addresses. The maxlength attribute is not used in these matches because it limits the maximum number of characters that can be entered, but none of the listed descriptions asks for character-length restriction. References/topics: HTML5 form attributes, constraint validation, pattern, placeholder, required, multiple, input validation.

First drop-down: flex boxes

Second drop-down: background-size

Third drop-down: cover

The layout changes from a stacked mobile layout to a multi-column desktop layout without relying on media queries. That behavior is commonly achieved with responsive flex boxes, where items can wrap naturally based on the available width. The header image must fill the available header area on both mobile and desktop. For that requirement, the correct CSS property is background-size, and the correct value is cover. background-size: cover scales the image so the entire header area is filled, even if part of the image is cropped. contain would preserve the full image but could leave empty space, and auto would keep the image at its natural size.

The correct markup is option D. The type= " tel " input type is appropriate for telephone-number entry, but it does not automatically validate a specific telephone-number format because phone formats vary internationally. MDN notes that tel inputs allow telephone entry but are not automatically validated to a particular format. Therefore, a pattern attribute is required to enforce the exact structure. The regular expression [0-9]{3}-[0-9] {3}-[0-9]{4} requires three digits, a hyphen, three digits, another hyphen, and four digits, matching the requested format such as 111-444-7777. MDN defines the pattern attribute as a regular expression the input value must match for constraint validation. The required attribute is also necessary because the field must not be empty; MDN states that required indicates the user must specify a value before the form can be submitted. Option A only limits length. Option B lacks hyphen validation and required. Option C hard-codes only specific digits. References/topics: HTML5 validation, tel, pattern, required, regular expressions.

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