I am reaching ______ to touch base on the latest updates.

• A. Out
• B. Up
• C. Across
• D. Over

Answer: (A)

The key idea here is using the phrasal verb reach out to mean contacting someone, paired with the idiom touch base that means to reconnect or check in about updates. In this sentence, the natural completion is reaching out to touch base, because reach out to is the standard way to indicate making contact with someone for a purpose, and touch base signals the intent to get the latest information. So I am reaching out to touch base on the latest updates reads as a clear, professional way to say you’re contacting them to get updates.

The other options don’t fit well because they don’t form the common collocation with touch base in this context. Up connotes a physical direction rather than making contact, while across and over imply different kinds of movement or crossing boundaries rather than initiating contact for an update.