It was possible for Adam to sin because God created him with free will. That gift is not at all in conflict with the fact that Adam was perfect.
वह इसलिए क्योंकि परमेश्‍वर ने आदम को आज़ाद मरज़ी दी थी, यानी वह अपने फैसले खुद कर सकता था ।