Tyrus Raymond Cobb was born in Narrows, Georgia in 1886. He grew up in Royston, Georgia with his parents, William and Amanda Cobb. Ty began playing baseball as a child and was a professional baseball player before the age of twenty. Cobb played mostly for the Detroit Tigers and served as their player manager from 1921～1926. He played baseball for a total of twenty-four years before retiring. Cobb won twelve American League batting titles and was known for his great speed and excellent batting skills. He used both of these as weapons on the baseball diamond. Cobb still holds the record as the all-time leading hitter in the major leagues, with a 367 lifetime batting average. His career total of 4 191 hits was the major league record until it was broken by Pete Rose in 1985.
Ty Cobb was elected to the Baseball Hall of Fame in 1936 and was one of the first five players to receive this award. Cobb died in Atlanta, Georgia on July 17, 1961 and will be remembered as the great "Georgia Peach".

Ty Cobb’s interest in baseball began ______.
[A] in Philadelphia.
[B] when he lived in Detroit.
[C] at the University of Georgia.
[D] as a young boy.

请补充main函数。该函数的功能是：求1～100(不包括100)以内所有素数的平均值。 程序运行后的结果为42.40。 注意：部分源程序给出如下． 请勿改动主函数main和其他函数中的任何内容，仅在 main函数的横线上填入所编写的若干表达式或语句。 试题程序： #include＜stdio.h＞ main() { int i, j, n=0，flag； float aver=0； clrscr()； for(j=2；j＜100；i++) {flag=1；for(i=2；i＜j；i++) if( 【1】 ) {flag=0；break； }if( 【2】 ){ n++； aver+=j；} } printf("\n\n average=%4.2f"， 【3】 )； }