Correct Answer: thrown

Solution : The fourth option is correct.

The verb thrown is the past participle of throw and should be used in the third conditional. The sentence implies that the action of throwing the cell on the bed had consequences, as she was unable to call him.

The other options do not fit the context.

• Through is a preposition and doesn't make any sense in this sentence.
• Throne is a noun, referring to a ceremonial chair for a king or queen, and doesn't make sense in the context.
• Throng is a noun, meaning a large, densely packed crowd, and doesn't fit in the context either.

Therefore, the correct sentence is: " If she hadn't thrown her cell phone on the bed, she could have called him."