3/5 x 2 5/6
= 3/5 x 17/6
= 51/30 (option c)
Now if we divide 3 from both numerator and denominator to get the simplest form, we get :-
17/10 (option b)
And by making 17/10 into a mixed fraction we get 1 7/10 (option d)
So options b, c and d all are correct.
Hope that helps !!