Choose the correct alternative which will improve the quoted part of the given sentence.
Make sure you 'contact with' as many teachers as possible.

contact with' হলো ব্যাকরণগত ভুল। 
The preposition 'with' means accompanied by (another person or thing).
Here in the sentence, 'contact' is an action that has to be done without accompanied by someone.
So, 'with' is inappropriate.
অতএব সঠিক বাক্য হবে, Make sure you contact as many teachers as possible.