React Danger: Abandoning Unexpected Node in Safari

I have the following react component. It works in Chrome, but in Safari it throws

Danger: canceling an unexpected node: <option value=​"1" data-reactid=​".0.1.3.0.0.1.1.1.0.1:​$vivienda.$1">​Apartamento​</option>​

import React from 'react';

export default class SelectorOptgroup extends React.Component{

getOptions(){
   let options = [];
for(let key in this.props.subOption){
 options.push(<option key={key} value={key}>{this.props.subOption[key]}</option>   );
}
return options;
}
render(){
  return (
  <optgroup label={this.props.label}>
    {this.getOptions()}
  </optgroup>
)
}
}