Determine bond length and bond strength?

Question

The picture of the problem is shown here:
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I got the following:
I think that the strongest bond is the triple bond (A).
I think that the shortest bond is also the triple bond (A).
I think that the longest bond is the single bond but I don't know which single bond is longer (C or D).
I think that the weakest bond is also the single bond but I don't know which one (C or D).

Any help? Thanks. :)