Select the most appropriate option to fill in the blank.

Marconi ______ the radio.

invented

The most appropriate option to fill in the blank is:

☀ invented

Explanation:

The sentence "Marconi invented the radio" indicates that Marconi is credited with creating or developing the radio. "Invented" is the correct choice here because it accurately conveys the idea of originating or creating something that previously didn't exist.

The other options have slightly different meanings:

• "Discovered" implies finding or uncovering something that already existed but was not previously known.
• "Built" and "assembled" refer to the construction or putting together of something, which might be a part of the radio's creation process, but "invented" best captures the concept of creating the radio technology itself.