Risk and uncertanty

Dear tutor,

Can u explain for me which of following is correct

A. Sensitivity analysis takes into account the interrelationship vw project variables ( false because isolating each variable once at a time)

B. Probability analysis can be used to assrss the uncertainty associated with the project
(Please explain for me whether true or false)

C. Uncertainty can be said to increase with project life, while risk increases with the variablilitt of returns
( i think this one is correct)

D. A discount rate of 5% could be used to lessen the effect of later cashflows on the decision
( please explain for me about this)