A coin has probability 'p' of showing head when tossed. It is tossed 'n' times. Let pₙ denotes the probability that no two (or more) consecutive heads occur. The value of p₄ is given by:
a) p₄
b) (1-p)³.p
c) (1-p)².p²
d) (1-p)³.(1+p)