You can zoom just like in any other window with the following mouse clicks:
[ol 1]
[li]position the cursor anywhere on the options tree;[/li]
[li]press and hold mouse button 2 (MB2) – the scroll wheel;[/li]
[li]press and release MB1 while keeping MB2 pressed;[/li]
[li]move the mouse up to zoom in;[/li]
[li]move the mouse down to zoom out.[/li]
[/ol]
Hope this helps,
Best of luck!
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CATIA v5 — user & trainer
ANSYS — user (beginner)
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