After Submitting a Proposal to a Customer, If No Limitations

Multiple Choice

After submitting a proposal to a customer, if no limitations for contact were stated in the RFP then the contractor should

A) wait until the customer contacts the contractor
B) research other firms that would have bid on the project and contact them to see if they had been contacted by the customer.
C) contact the customer to see if any clarifications are needed or any questions need to be answered.
D) send a thank you note in the mail to the customer.