Answer:
C. Potassium/argon dating
Step-by-step explanation:
When it comes to dating old objects, science use a variety of methods, most of them based on known and stable physical/chemical reactions.
A. Principle of inclusions states that if you basically find a rock inside another rock, the inner one is older. Doesn't help in this case.
B. Uranium/lead dating is used to date very very old stuff, like more than a million years old, up to 4.5 billions years - the age of our planet. If I suspect the rock is about 200,000 years, this won't do.
C. Potassium/argon dating is used to date rocks that are older than 100,000 years, so this would be the good technique to use.
D. Carbon/nitrogen dating is use to date stuff ranging from about 5,700 years to 50,000 years. Not useful in this case.