html – Bootstrap bottom alignment

Question:

How to align all images to the bottom if all images have different heights?

<div class="row">
  <div class="col-xs-3">
    <img class="img-responsive" src="img1.png" alt="">
  </div>
  <div class="col-xs-3">
    <img class="img-responsive" src="img2.png" alt="">
  </div>
  <div class="col-xs-3">
    <img class="img-responsive" src="img3.png" alt="">
  </div>
  <div class="col-xs-3">
    <img class="img-responsive" src="img4.png" alt="">
  </div>
</div

Answer:

.img-responsive {
  position: relative;
  bottom: 0;
}

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