Why is this the answer?

The answer is violin because this clever riddle describes the look and sound of a wonderful musical instrument. Let us look at the clues one by one! First, the riddle says, "My voice is tender." This is a perfect way to describe the beautiful sound a violin makes. A violin can make soft, sweet, and gentle music, which is why the riddle uses the word "tender" for its voice. It is a lovely, singing sound that people enjoy hearing, especially in orchestras and classical music performances. Next, the riddle says, "my waist is slender." Think about the shape of a violin. It is a stringed instrument that has a very thin or narrow middle part. This shape is what gives it the lovely, curving sides that make it look graceful. The word "slender" means thin or gracefully slim, which is exactly how the body of a violin is designed. Its shape helps it to make its beautiful sound. Then, the riddle tells us, "and I am often invited to play." Violins are extremely popular musical instruments. They are used in big groups called orchestras, in small chamber music groups, and sometimes people even play them all by themselves for concerts. Because the music they make is so wonderful, the violin is constantly being asked, or invited, to be a part of many different kinds of musical events. The final and most important clue is, "Yet wherever I go, I must take my bow or else I have nothing to say." This is the best clue of all! A violin needs a special stick with horsehair on it called a bow. The musician must rub the bow across the strings of the violin to make the music. If the violin is played without the bow, it cannot make that beautiful music, so it truly would have "nothing to say." The riddle cleverly uses the word "bow" in a tricky way, referring both to the tool and the action a musician might take after a performance. All these clues point directly to the violin. It is an instrument with a beautiful voice, a slim shape, and it always needs its trusty bow to sing.