单项选择题

The buyer of a certain mechanical toy must choose 2 of 4 optional motions and 4 of 5optional accessories．How many different combinations of motions and accessories are available to the buyer（）

A. 8
B. 11
C. 15
D. 20
E. 30

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单项选择题
A certain computer program generates a sequence of numbers P1，P2，……Pn，by the rules P1=1，P2=1，and for n≥3，Pn=Pn+1+pn-2，Which of the following equals P5（）

A. 10
B. 11
C. 14
D. 15
E. 17
单项选择题
If for a given spin，the pointer shown in the figure above is equally likely to stop on any of the numbered sectors，what is the probability that the pointer will stop on an odd-numbered sector(Assume that the pointer cannot stop on a dividing line between sectors．)（）

A.A
B.B
C.C
D.D
E.E
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