is it B ?

H+H'P'(AUB)H+H'P'(AUB)H'P'(AUB)H+..... Here PROB OF GETTING 5 OR 6 ON DICE = 1/6+1/6 =1/3 AND NOT OF THIS LET P'(AUB)= 1-1/3=2/3

1/2+1/2*2/3*1/2+1/2*2/3*1/2*2/3*1/2+....

= 3/4

H+H'P'(AUB)H+H'P'(AUB)H'P'(AUB)H+..... Here PROB OF GETTING 5 OR 6 ON DICE = 1/6+1/6 =1/3 AND NOT OF THIS LET P'(AUB)= 1-1/3=2/3

1/2+1/2*2/3*1/2+1/2*2/3*1/2*2/3*1/2+....

= 3/4