JSFiddle - React, Tailwind, and code Playground

HTML

<div class='select-wrapper'>
<select class="selectClass">
  <option value="">Option 1</option>
  <option value="">Option 2</option>
  <option value="">Option 3</option>
  <option value="">Option 4</option>
  <option class='option-5' value="">Option 5</option>
  <option value="">Option 6</option>
  <option value="">Option 7</option>
</select>
</div>

CSS

.select-wrapper {
  position: relative;
  display: block;
  font-size: 16px;
}

.selectClass {
  position: relative;
  display: block;
    font-size: 96px;
    text-transform: uppercase;
}

.selectClass option {
    font-size: 16px !important;
}

.selectClass .option-5 {
    font-size: 16px !important;
}