一个最简真分数，分子和分母的和是15，这样的分数有[ ]
A.2个
B.3个
C.4个
答案：C
—Who called just now, Sam?
—It’s Mona. She asked _____.
A．that Peter was in
B．if was Peter in
C．if Peter was in
D．whether was Peter in
烧伤后发生十二指肠粘膜的糜烂、溃疡、出血等，称为________溃疡。
