Pre-select option from state object React.js

Hi there,

I'am trying to pre-select on option from my form state object but cannot manage to render it. As an example, doing this works if I use a string:

class SelectPage extends Component {
  render() {
    return (
      <div>
        <MDBSelect>
          <MDBSelectInput selected="Choose your option" />
          <MDBSelectOptions>
            <MDBSelectOption disabled>Choose your option</MDBSelectOption>
            <MDBSelectOption value="1">Option nr 1</MDBSelectOption>
            <MDBSelectOption value="2">Option nr 2</MDBSelectOption>
            <MDBSelectOption value="3" selected={_id === "456ef-78e78-feff56"}>Option nr 3</MDBSelectOption>               
          </MDBSelectOptions>
        </MDBSelect>
        <label>Example label</label>
      </div>
    );
  }
}

But this doesn't when I use the state object:

class SelectPage extends Component {
  render() {
    return (
      <div>
        <MDBSelect>
          <MDBSelectInput selected="Choose your option" />
          <MDBSelectOptions>
            <MDBSelectOption disabled>Choose your option</MDBSelectOption>
            <MDBSelectOption value="1">Option nr 1</MDBSelectOption>
            <MDBSelectOption value="2">Option nr 2</MDBSelectOption>
            <MDBSelectOption value="3" selected={_id === this.props.myId}>Option nr 3</MDBSelectOption>
            <MDBSelectOption value="4">Option nr 4</MDBSelectOption>
            <MDBSelectOption value="5">Option nr 5</MDBSelectOption>
          </MDBSelectOptions>
        </MDBSelect>
        <label>Example label</label>
      </div>
    );
  }
}

Here this.props.myId come from my form state object and passed to the component via props. On Chrome's react.js developer tools the this.props.myId is populated correctly.

The only thing I really want to do is this below but I cannot manage to do it with the MDB react select component:

<select value={optionsState}>
  <option value="A">Apple</option>
  <option value="B">Banana</option>
  <option value="C">Cranberry</option>
</select>

Thanks in advance for your help.