Data Sufficiency (DS) | Re: Is wp+st>0?

It can not be C.
1) ws+pt>0
clearly Insufficient.

2)wt+ps>0
clearly Insufficient.

Now add these two inequalities
ws+pt+wt+ps>0
ws+wt + pt+ps >0
w(s+t) + p(s+t)>0
(w+p)(s+t)>0

still nothing is clear. Hence statements 1 and 2 together are not sufficient.

Hence Answer is E.
Kudos if it
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