The line in option A shows the main idea of the paragraph in which we read what some scientists belive about yawning: being a form of communication, they theorize trying to understand why yawning seems to spread from person to person, considering this a form of communication, with a contagious form of message, even though they are not yet sure what it is.
C. On the day of my piano recital, I was experiencing nervousness.
In expository writing, a topic sentence is a sentence that summarizes the main idea of a paragraph. It is usually the first sentence in a paragraph. Also known as a focus sentence, it encapsulates or organizes an entire paragraph.
Some people might not have saved a lot of money during their time working. Therefore, not having enough funds saved up in order to retire. Things are also more expensive than they used to be, causing old people to spend more money.
Marketers can take advantage of celebrity appearances to market their products, services, or brand simply by being more intentional about such appearances.
Celebrity branding or marketing or endorsement is a form of strategy in marketing where a company leverages off the strength of a celebrity's brand to create an appeal for its own.
When businesses want to launch a product for instance, instead of counting on the goodwill of celebrities to attend, they can intentionally create a situation that makes it conducive for them to appear.
This can be achieved by:
Paying the celebrities to make an appearance
giving them a special space properly branded with the product or service for giving autographs etc
inviting at least one other celebrity with whom they have a great relationship
One example of a business that uses celebrities to attract customers to an event is World Wrestling Entertainment (WWE).
Occasionally, WWE invites Hollywood celebrities as a commentator at its main events.