33.
(A) having significant larger dips
(B) with significantly larger dips
(C) had significantly larger dips 
(D) dipped significant larger

這題考的是對等子句的結構

The groups had little difference in walking blood pressure, but married people           in blood pressure during sleep.

but是對等子句連接詞，連接兩個完整的子句，且對等子句的兩個句子需保持時態一致(過去式)

所以只要把這句挑出來，用一般的文法規則看就行了：married people           in blood pressure during sleep

(A) having significant larger dips → have，用having會使的這個句子沒有動詞

(B) with significantly larger dips → 用介系詞片用的話，會被視為做形容詞用的主詞補語，這樣會使的這個句子沒有動詞

(D) dipped significant larger → 這兩個詞修飾的對象是動詞dipped，所以應該改成副詞significantly and more largely