Answer:
a)  Parents Genotype should be (CC,Vv) and (cc,VV).
b) The genotypes of the parents are (Cc,Vv) and (Cc,Vv).
c) The genotypes of the parents are (Cc,Vv) and (cc,vv).
Explanation:
<h2>                                      (<u>a)</u> </h2>
Mating has occured between a normal colored mice whose genotype is C_,V_  and normal white  mice with genotype cc,V_. The offsprings are as follows : 
1) normal mice produced 29 colored 
2) 10 colored, waltzing progeny. 
Thus all offspring are normal. The genotype of the first parent should therefore be CC. Waltzing trait is produced. The V gene should therefore be heterozygous in both traits. 
Hence The parent genotypes should be<u> (CC,Vv) and (cc,CV).</u>
<h2>                                      (b)</h2>
 In this case the approximate ratio in which the descendants are produced is 9:3:3:1. Hence genotypes of the parents are <u>(Cc,Vv) and (Cc,Vv).
</u>
<h2>
                                      (<u>
c)</u>  </h2>
In this case the approximate ratio in which the offsprings are produced is 1:1:1. The genotypes of the parents are <u>(Cc,Vv) and (cc,vv).
</u>