根据句意用括号内所给单词的适当形式填空：

1. A woman ______ Anna Jarvis started Mother's Day in early 1990s. (name)

2. Mr Liu says that the Internet is the most important ______ since the printing press. (invent)

3. Russia is the ______ in area and in population in Europe. (big)

4. He can ______ learn a lot about where I live. (real)

5. There is ______ metal than plastic. (little)

患者，女性，28岁，因"左下颌下区肿胀3个月"入院，患者3个月前出现左下颌下区肿胀，不适，无疼痛、麻木，与进食无明显关系。检查：左颌下区肿胀，皮肤无红肿、破溃，皮温正常，触之质韧，无明显波动感。口内检查见双侧下颌下腺导管口无红肿，分泌液清亮。

若怀疑口外型舌下腺囊肿时，以下哪项检查结果可以作出诊断（）

A.穿刺见黄绿色液体

B.穿刺见蛋清样液体

C.下颌下区肿物切取活检

D.舌下腺切取活检

E.超声检查见单囊性无回声区