Peering about constantly at the entrance of its burrow, the lively meerkat is a ___ guardian of its home. A. auspicious B. ostentatious C. vigilant D. visionary

The meerkat is displaying behaviour which is attentive and it is being proficient with its job. Out of the four options, ostentatious means pretentious, or showing display, which is incorrect. Auspicious means "favorable to success" and this does not fit here. Visionary would indicate something with a future aim, which the meerkat is not. Finally, vigilant means to keep careful watch, making C the best answer.