JSFiddle - React, Tailwind, and code Playground

HTML

<select id="select1" >
	<option value="apple" selected >Яблоко</option>
	<option value="pear" >Груша</option>
</select>
<select id="select2" >
	<option value="apple" >Яблоко</option>
	<option value="pear" selected >Груша</option>
</select>

JavaScript

$(function(){
	$("#select2").change(function(){ 
		if($(this).val() == "apple")  $("#select1").val("pear")  
	});
});