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A riddle:

• It's a sign of manhood, but it's not a mustache.
• It's another name for safety, but, no, it's not a helmet.

These are the first two lines of a four-line riddle that's part of a media contest in India that aims to get men talking about sex. Launched in time for World AIDS Day on December 1, the campaign hopes the riddle is intriguing enough that it actually gets men to talk with their friends about topics that can be rather awkward to discuss. 

Many HIV/AIDS prevention campaigns simply tell people to talk about sexual health, but this one actually stimulates people to do so. Additionally, to be eligible to win a prize, people have to call in and actually say the one-word answer to the riddle—no text-messaging the answer allowed! Prizes, such as mobile phones with free minutes, continue the theme of promoting talking.

The contest, sponsored by the BBC World Service Trust, targets men in four southern Indian states that have higher HIV rates. Why men? Research shows that if you can get men to talk about sex and condoms, they're more likely to be consistent condom users. (Did I just give away the answer to the riddle?)