Final answer:
The word that completes the sentence is 'Ingot'. It refers to a solid block of gold, which was not taken during the murders.
Step-by-step explanation:
The word that completes the sentence is d) Ingot. An ingot is a mass of metal, typically shaped like a rectangular prism. In the context of the sentence, it refers to a gold ingot, which is a solid block of gold.
The sentence is stating that it was strange that the money and the gold ingot were not taken during the murders. This suggests that the thieves may have had a specific motive for the murders and were not interested in stealing the valuable gold ingot.
Therefore, the correct answer is d) Ingot.