The structure of this animal's brain given no     that it is any more intelligent than others.

A. hint   B. indication   C. intimation   D. implication

hint: a hint is a suggestion about something that is made in an indirect way

indication: a sign that something exists, is true, or is likely to happen 

               Helen's face gave no indication of what she was thinking.

intimation: an intimation is an indirect suggestion or sign that something is likely to happen or be true. 

implication: the implication of a statement, event, or situation is what it implies or suggests is the case.

这些英文释义是柯林斯上找的，但还是有些疑惑，尤其是对这道题来说，hint 和 indiction 哪一个更合适？

请各位老师帮忙解答