How to change font size of select list material ui?

Question

React

How to change font size of select list material ui?
How to access .MuiMenuItem-root?

<FormControl variant='outlined' className={classes.select}>
                <InputLabel id='demo-simple-select-outlined-label'>Month</InputLabel>
                <Select
                  labelId='demo-simple-select-outlined-label'
                  id='demo-simple-select-outlined'
                  value={age}
                  onChange={handleChange}
                  label='Month'
                  IconComponent={ArrowDownIcon}
                >
                  {months.map((month, inx) => (
                    <MenuItem key={month} value={inx + 1}>
                      {month}
                    </MenuItem>
                  ))}
                </Select>
              </FormControl>

select: {
      marginRight: '10px',
      '&:first-child': {
        minWidth: '250px',
      },
      width: '100%',

      '& label': {
        fontSize: '17px',
      },
      '& .MuiSelect-outlined': {
        padding: '14px 35px 14px 15px',
      },
      '& .MuiSelect-root': {
        fontSize: '17px ',
      },
      '& .PrivateNotchedOutline-root-26': {
        padding: '0 2px',
      },
      '& .MuiSelect-icon': {
        right: '8px',
      },
      '& .MuiSelect-iconOpen': {
        color: 'rgb(29, 161, 242)',
      },
    },