Which one of the following is the correct output for the given JavaScript code?
<ol class="dp-xml" start="1">
 	<li class="alt">const <span class="attribute">object1</span> ={};</li>
 	<li class=""><span class="attribute">a</span> = <span class="attribute-value">Symbol</span>('a');</li>
 	<li class="alt"><span class="attribute">b</span> =<span class="attribute-value">Symbol</span>.for('b');</li>
 	<li class="">object1[a]='harry';</li>
 	<li class="alt">object1[b]='derry';</li>
 	<li class=""><span class="attribute">constobjectSymbols</span>=<span class="attribute-value">Object</span>.getOwnPropertySymbols(object1);</li>
 	<li class="alt">console.log(objectSymbols.length);</li>
</ol>