Read the compound sentence.
Which is the correct way to punctuate the sentence?
Dr. Burke wanted to trust her assistant with the secret
formula but she was afraid her assistant was a spy.
Dr. Burke wanted to trust her assistant with the secret
formula, but she was afraid her assistant was a spy.
Dr. Burke wanted to trust her assistant, with the secret
formula: but she was afraid her assistant was a spy.
Dr. Burke wanted to trust her assistant with the secret
formula but, she was afraid her assistant was a spy.
Dr. Burke wanted to trust her assistant with the secret
formula, but she was afraid her assistant was a spy.
O