-What did your parents think about your decision?

-They always let me do          I think I should.[ ]

A.when

B.that

C.how

D.what

某小企业通过技术创新，增强产品的新颖性、实用性，它实施的竞争战略属于（）

A．差异化战略 

B.低成本战略 

C.创新战略 

D.市场细分战略