Hello, MDBSelect is not working as expected. i already import all the css and bootstrap link and follow the instruction into the quick start guide. I also tried to use the PRO component option from the docs like https://mdbootstrap.com/docs/react/sections/e-commerce/ but all of them is working fine. except this MDBSelect. can someone pls help me with my issue? Thanks a lot!

import React, { Component } from 'react'; 
import { MDBContainer, MDBRow, MDBCol, MDBBtn, MDBSelect } from 'mdbreact'; 
class UserProfilePage extends Component {
state = {
    options: [
        {
            text: "Male",
            value: "1"
        },
        {
            text: "Female",
            value: "2"
        }
    ]
};

render(){
    return(
        <MDBContainer className={[classes.backgroundInfo, "p-4"].join(" ")}>
            <MDBRow className={["p-2", classes.titlePage].join(" ")}>
                <MDBCol className={["text-uppercase"].join(" ")}>My Profile</MDBCol>
            </MDBRow>
            <MDBRow className={["text-uppercase p-2"].join(" ")}>
                <MDBCol>
                    <small>Full Name</small>
                    <div>{this.props.fullName}</div>
                </MDBCol>
                <MDBCol>
                    <small>Birthday</small>
                    <div>MM-DD-YYYY</div>
                </MDBCol>
            </MDBRow>
            <MDBRow className={["text-uppercase p-2"].join(" ")}>
                <MDBCol>
                    <small>Mobile Number</small>
                    <div>xxx-xxx-xxxx</div>
                </MDBCol>
                <MDBCol>
                    <small>Gender</small>
                    <div>
                        <MDBSelect
                            options={this.state.options}
                            selected="Choose your option"
                            label="Gender" />
                    </div>
                </MDBCol>
            </MDBRow>
            <MDBRow className={["text-uppercase p-2"].join(" ")}>
                <MDBCol>
                    <MDBBtn className={classes.editInfo}>Edit</MDBBtn>
                </MDBCol>
            </MDBRow>
        </MDBContainer>
    )  }  }