Refer to the diagram above for this question.

The flip$-$flop FF$2$ has a hold time requirement of $100$ psec.

The clock tree buffers between point A and B have a total delay of $300$psec.

The combinatorial block between point $C$ and $D$ has a total delay of $1\mathrm{.}5nsec.$

If the positive clock edge is launched from point $A$ at time $T=2nsec,$ what is the earliest time the

data can change at point C $($the output of FF$1),$ in order to meet the hold time of FF$2.$

$T=150$ psec

$T=650$ psec

$T=800$psec

$T=900$ psec