Step-by-step explanation:
This is a probability related question, let the event be E
We know that the likelihood of an event happening is given as
Pr(E)=1
if an event will not occur the probability is
Pr(E)=0
a. This event is impossible: Pr(E)=0
b.This event will occur more often than not, but is not extremely likely:
Pr(E)=0<E>0.5
c.This event is extremely unlikely, but it will occur once in a while in a long sequence of trials:
Pr(E)=0<E<0.5
d.This event will occur for sure: Pr(E)=0