Step 1: Think about the stage of the product.
A brand new product has no buyers yet and no reputation. People first need to know it exists. So the advertisement must mainly inform.
Step 2: Link the stage to an advertising type.
Advertising at the launch stage of a product life cycle is called informational or pioneering advertising. Its job is to build awareness, not to push people to switch brands.
Step 3: Test option 1 against this idea.
Institutional advertising speaks for the whole company and its values. A launch ad speaks for one product. Option 1 does not fit.
Step 4: Test option 2 against this idea.
Cooperative advertising is a cost-sharing arrangement between partners. The question asks about purpose at launch, so option 2 does not fit.
Step 5: Test option 3 against this idea.
Informational ads are built to explain a product to people who have never seen it. This fits the launch situation exactly, so option 3 fits.
Step 6: Test option 4 against this idea.
Cross promotion is a tie-up where two brands help sell each other. It can be used at any stage, so it is not the answer here.
Final Answer:
The launch of a new product calls for informational ads, so the key is option 3.
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