Science subject demonstrate observation
Social welfare department observation
Reported or indirect speech is usually used to talk about the past, so we normally change the tense of the words spoken. We use reporting verbs like 'say', 'tell', 'ask', and we may use the word 'that' to introduce the reported words. Inverted commas are not used.
Answer: C. Their camera
Toolmarks are the impressions left by an object or tool on it's contact surface. Toolmarks are searched and collected in a crime scene to relate a link with the tool which has created them. In crime scene investigation, toolmarks found in the scene of crime should be photographed by the analyst in close range, mid range and overview range shots in order to record it's original location, shape, size and number if multiple tool marks are present.