And, Also, Too, However

Posting your address on social media is dangerous, and you should also keep your ID number a secret. The word "too" is used to indicate that keeping your ID number a secret is an additional action that should be taken, in addition to not posting your address.

The correct answer is "He knows how to download free apps. He also reviews these apps after using them." This answer effectively connects the two separate sentences by using the conjunction "also" to show that the action of reviewing the apps is in addition to the action of downloading them.

The correct answer is a valid explanation for the given question. It connects the ideas of having no money in the bank account and never sharing the ATM password using the conjunction "however". This suggests that despite not having any money, the person still maintains the security of their account by not disclosing their password to anyone.

The correct answer is "My mom uses online banking. She does online shopping, too." This answer uses the word "too" to connect the two separate sentences about the actions of the mom. It indicates that in addition to using online banking, she also engages in online shopping.

The correct answer is a concise and grammatically correct sentence that combines the two ideas of Jane creating a Facebook account and a Line account. It eliminates repetition and effectively conveys the information in a single sentence.