One might infer that these diseases were the result

a. competition for space

b. lack of pollinators

c. introduced species

d. poor tree husbandry

One might infer that these diseases were the result of introduced species

Option C

Explanation:

Introduced species are the new species that are introduced to a new environment taken away from their home. It might have occurred due to natural occurrence or by physically introducing it to a new environment.

There are several examples citing the introduced species like bio control species to prevent using pesticides on plants. There are also chances for the newly introduced species to interact with the native species to produce hybrids which results in Genetic diversity. But certain times due to the introduction into the new environment it is highly prone to diseases.

preservation because he preserves part of the land and preserves means save

explanation:

check for the pregnancy rating of drug. if its class c or d see if other alternatives