You can sell a straddle, or, in other words, enter a short position in a straddle, if you predict markets to calm down (volatility to decrease) and you are not sure of the general trend. Short straddle consists of short positions in a call and a put of the same strike and expiry.
See also strangle.
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The screenshot shows the following portfolio:
European call struck at 11.000 with expiry in 30 days
European put struck at 11.000 with expiry in 30 days
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