When I run cgminer for run it to mine ltc the parameter --scrypt, cgminer says that is not recognized option. So, cgminer does not work.
What miner can I use to mine litecoin with the scrypt hash function?
You can look at this table of software scrypt miners.
You don't mention whether you intend to try to use a CPU or GPU to mine. Towards the top of the list is sgminer (for GPU mining) and Pooler's cpuminer (for CPU mining). There are other choices listed there, but a number of them are just graphical frontends or are listed as no longer maintained.