Bootstrap Quality Control & Assurance 4

Question 1

A responsive layout QA test fails on tablets but passes on mobile and desktop. Which Bootstrap breakpoint range covers tablets by default?

Accepted Answer

md (≥768px) to lg (≥992px)

Answer

Tablets typically fall in the md (768px) to lg (992px) Bootstrap breakpoint range.

Question 2

Which Bootstrap grid utility hides an element only on medium screens (md) while keeping it visible on all other sizes?

Accepted Answer

.d-md-none

Answer

.d-md-none sets display:none starting at the md breakpoint without affecting other breakpoints when combined with .d-block.

Question 3

During cross-browser QA, Bootstrap's flex utilities render incorrectly in an older browser. Which CSS feature do Bootstrap's .d-flex and .flex-* classes depend on?

Accepted Answer

CSS Flexbox

Answer

Bootstrap's .d-flex and all .flex-* utilities are built on the CSS Flexbox specification.

Question 4

A QA engineer checks that columns stack vertically on mobile. Which Bootstrap column class produces a full-width column only on extra-small screens?

Accepted Answer

.col-12

Answer

.col-12 spans all 12 grid columns at every breakpoint including xs (extra-small), making it full-width on mobile.

Question 5

When auditing Bootstrap's container widths, which container type spans the full viewport width at every breakpoint?

Accepted Answer

.container-fluid

Answer

.container-fluid is always 100% wide regardless of viewport size, unlike .container which has max-width breakpoints.

Bootstrap Practice Test

Bootstrap Practice Test

Bootstrap Quality Control & Assurance 4