A Veterinarian Wants to Know Whether German Shepherd Dogs in Ontario

A veterinarian wants to know whether German Shepherd Dogs in Ontario are heavier or lighter than the average weight of that breed as documented in international records. Why will he probably use a one-sample hypothesis test?

A) Other types of hypothesis tests require a null hypothesis, but there cannot be one for this research scenario.
B) The scenario implies a one-tailed test, and only the one-sample hypothesis test allows this decision.
C) There is no population specified by this scenario, and one-sample hypothesis tests require only samples rather than populations.
D) It is more realistic for him to obtain a sample of Ontario German Shepherd Dogs than to obtain the population parameter.