Question

complete the sentence with the best relative pronoun. the invasion of asian toads threatens madagascars unique ecology, is vulnerable to outside predators and diseases. submit

Explanation:

In this sentence, we need a relative pronoun to introduce a non - restrictive relative clause. The antecedent is "Madagascar's unique ecology", which is a thing. "Which" is used for non - restrictive relative clauses when the antecedent is a thing. "That" cannot be used in non - restrictive relative clauses. "Who" is for people. "Whose" is used for possession.

Answer:

which