Will background verification from potential employer lower my credit score?

I am looking for a job. Each company asks for background verification disclosure prior to my interview. So far there are about 3 already. I am very worried that if each one of them does a credit inquiry on me, my credit score will be substantially lowered. I am wondering if anyone had problem similar like this and how to solve it? We want to keep the credit as high as possible to obtain a mortgage later on.