In Drosophila, the Genes B, C, and Sp Are Linked

question 35

Multiple Choice

In Drosophila, the genes b, c, and sp are linked and arranged as shown below: b--30 m.u.--c--20 m.u.--sp
This region exhibits 90% interference.How many double crossovers would be recovered in a three-point cross involving b, c, and sp out of 1000 progeny?

• A)3
• B)6
• C)54
• D)60
• E)600