Seven friends A,B,C,D,E,F and G, each has a different height. A is shorter than B but taller than C. B is taller than only four others. E is taller than G but shorter than C. D is taller than B but shorter than F. Who is the tallest among all?

F

From the given information:

Step 1: A is shorter than B but taller than C.

So, B> A> C

Step 2: E is taller than G but shorter than C.

So, C> E> G

Step 3: D is taller than B but shorter than F.

So, F> D> B

Combining the given information:

So, F> D> B> A> C> E> G

Thus, F is the tallest.