I have installed Raspbian via NOOBS.
So this is the one and only OS in my SD card.
But I always found myself at the OS selection screen every boot, and I have to wait 10 second to boot to Raspbian.

Is there a way to turn off this OS selection screen?

Is it enough to delete `/boot/os_config.json`?

EDIT:

My boot screen shows only one entry.

`/boot/os_config.json` file contains:

```
[
  {
    "bootable": true,
    "description": "A port of Debian jessie for the Raspberry Pi (full desktop version)",
    "folder": "/settings/os/Raspbian",
    "icon": "/settings/os/Raspbian/icon.png",
    "name": "Raspbian",
    "partitions": [
      "/dev/mmcblk0p6",
      "/dev/mmcblk0p7"
    ],
    "release_date": "2017-07-05",
    "supported_models": [
      "Pi Model",
      "Pi 2",
      "Pi Zero",
      "Pi 3"
    ]
  }
]

```

`sudo cfdisk /dev/mmcblk0` shows:

```
Free space              2048     8191     6144    3M                 
/dev/mmcblk0p1          8192   137215   129024   63M  e W95 FAT16 (LB
/dev/mmcblk0p2        137216 31116287 30979072 14.8G  5 Extended
├─/dev/mmcblk0p5      139264   204797    65534   32M 83 Linux
├─/dev/mmcblk0p6      204800   339967   135168   66M  c W95 FAT32 (LB
├─Free space          342016   344064     2049    1M                 
└─/dev/mmcblk0p7      344064 31116287 30772224 14.7G 83 Linux

```