JSFiddle - React, Tailwind, and code Playground
HTML
<span class="price">
$20
</span>
<p id="in-cart" style="display: none;">in cart</p>
<span class="needsclick select-widget enabled" id="size-options-link">Medium</span>
<select id="size-options" name="size-options" class="select-widget ">
<option value="46158">Medium</option>
<option value="46159">Large</option>
<option value="46160">XLarge</option>
</select>
<span id="cart-update"><span class="cart-button">add to cart</span></span>
JavaScript
var option = $('#size-options').find('option:contains(Large)')[1];
$(option).prop('selected', true);