Out of 800 progeny of a three-point testcross (testcross for a heterozygote for all three loci) there were 16 double crossovers, whereas 80 had been expected on the basis of no interference (Hint: each double CO produces two double recombinants). The interference is:_________
a. 0.690
b. 0.310
c. 0.655
d. 0.090
e. 0.045