Select the most appropriate option to fill in blank number 5.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4, i.e. “poison.”
The sentence in context reads:
“…the frogs are frequently referred to as poison arrow frogs or poison dart frogs.”
It mentions how indigenous people use the frogs' toxic secretions to poison the tips of arrows and darts. This is directly confirmed by sources explaining the origin of their common name—for example:
“These amphibians are often called ‘dart frogs’ due to the Amerindians' indigenous use of their toxic secretions to poison the tips of blowdarts.”
None of the other options fit this meaning; only “poison” accurately describes the action.