单项选择题吴女士,34岁,已婚,有2次人工流产史,在妇科疾病普查时被诊断为慢性宫颈炎,该病的主要临床症状是 A. 腰骶部疼痛 B. 白带增多 C. 不孕 D. 月经失调 E. 下腹坠痛
不定项选择A marketing channel overcomes the time, place, and possession gaps that separate goods and services from those who need or want them.