Question

researcher joel berger wanted to know how the herd movement of arctic musk oxen might be affected by potential threats. since these large mammals fear bears, he made a costume that resembled a grizzly bear. he wore a long fur coat while carrying what looked like a giant teddy bear head. he then crept toward the unsuspecting musk oxen. the musk oxen became agitated at the sight of bergers disguise. this wasnt the only occasion that his research involved imitating a wild bear. berger also conducted tests using a polar bear costume. if he suspected the animals might charge, he tossed the polar bear mask into the air, revealing himself to be harmless. bergers experiments blank the animals. mesmerized classified sequestered deceived

Explanation:

The text describes Joel Berger using bear - like costumes to mimic threats to musk oxen. The animals were agitated by his disguise, meaning they were tricked into thinking a real threat was present. "Deceived" means to be misled or tricked, which fits the situation where Berger's experiments made the animals believe there were bears around.

Answer:

D. deceived