Whether you're in front of a group or across the desk, you want the best possible chance for your proposal to succeed.
What to do
Take control and expand your options. Here's an example:
Question: "Do you think we can get the contract if we come in under $100,000?"
Answer: "I don't believe the decision will be based solely on price. I believe the client's impression of our credentials, experience, and client list will be equally important."
Other responses to get out of a binary question:
"The situation is complex and requires more than a yes or no answer."
"Since you are asking me, I think we have more options than either Greenville or Compton. We might even consider putting the next office in the midwest. Let's review the criteria."
On-the-job application: Stay in control. Don't allow others to force you into a limited response if it won't do justice to the situation. Either/or locks you into two choices. When was the last time a major issue only had two possible solutions?