Bootstrap select error

I just want a form with an input and a select, but bootstrap is doing me this.

      <div class="form-group row">
             <div class="form-group col-md-6">
              <label for="inputEmail4">Morada</label>
              <input type="email" class="form-control" id="inputEmail4" placeholder="Email">
              </div>
              <div class="form-group col-md-6">
                 <label for="inputEstado">Estado:</label>
                 <select class="form-control" id="inputEstado" value="Agendado">
                      <option >Agendado</option>
                      <option >Por Marcar</option>
                      <option >Falta Material</option>
                      <option >Inspeção</option>
                      <option >Faturado</option>
                      <option >Ligado</option>
                      <option >Recebido</option>
              </div>
         </div>