Which of the following statements is/are correct regarding Barchan ? 1. It is a crescent-shaped sand dune which is deposited in a desert when the wind blows consistently in one direction. 2. The windward side has a convex steep slope and maximum height is in its middle. 3. The two ends of Barchan are called horns and they indicate the direction opposite to the wind flow. Select the answer using the code given below :

Barchans are crescent-shaped sand dunes formed in deserts when wind blows consistently from one direction, so statement 1 is correct. However, the windward side of a barchan has a gentle convex slope (not steep), and the leeward side is steep and concave; the maximum height is at the centre but the description of 'convex steep slope' is incorrect, so statement 2 is wrong. The two pointed ends called horns point in the direction of the wind flow (leeward direction), not opposite to it, so statement 3 is also incorrect. Hence only statement 1 is correct.