Answer:
1. A
2. B
3. A
Answer analysis:
1.tā nà jiāndìng de xìnxīn gǎnrǎn le wǒmen
他那坚定的信心感染了我们。
His firm faith infected us.
2.tā bǎ xīnguān bìngdú chuánrǎn gěile tā de jiārén
她把新冠病毒传染给了她的家人。
She transmitted the coronavirus to her family.
3.xīnguān bìngdú gǎnrǎn le hěnduō rén.
新冠病毒感染了很多人。
The coronavirus has infected many people.