<p>That college knows about your interest in it, perhaps because you listed it on the Common Application (if the email to you mentions the Common Application), but that doesn’t mean the college knows what other colleges you are interested in. (That also doesn’t mean the college CARES where else you are applying, but that issue still needs to be developed more in this thread.) BUT, if the college in question accepts the Common Application, and you have made any other inquiry with that college, even this inference is suspect, because of course the college will urge you to finish your Common Application and apply. </p>
<p>Try an experiment. Use your favorite email program to send “blind carbon copies” of the same email to several of your friends. If they reply, you can be pretty sure each recipient received your email. But if you really put the list of recipients on the blind carbon copies line, you could ask each recipient, “Do you know who else I sent this email to?” See by individual follow-up replies how many recipients can give you the EXACT LIST of recipients you set up at first.</p>