is suitable Ubuntu 14.04 LTS for general purpose?

Hi, I’m making Autonomous Drone With Jetson Tegra K1 Board.

I found out that My TK1 board’s ubuntu version is Ubuntu 14.04 LTS.

but, as far I know, Ubuntu 16.04 LTS is the latest Ubuntu LTS version.

Do I have to install Ubuntu 16.04 LTS on My TK1 board?

I’ll just install ZED SDK and OpenCV and Python DroneKit Library.
(Stereo Camera Drone for Object Tracking)

in this purpose, will it be okay?

“Linux for Tegra” is an Ubuntu system with hardware access files added. The JTK1 arrives with Ubuntu 14.04, but the most current L4T (R21.5) for JTK1 uses Ubuntu 16.04 LTS. You can flash this. I do not know what your other applications actually work with or require.

If you choose to flash you can either flash on command line by downloading the driver package and sample rootfs (documentation suggested), or JetPack (JetPack is a front end to flash and installing software…it requires running on an x86_64 Linux host with Ubuntu 14.04…though some people use it with Ubuntu 16.04 on the PC host). See:
https://developer.nvidia.com/linux-tegra-r215