Server's chain certificate verification failed in azure Client

Question

I am trying to run my IoT-client on Threadx-Os Client which doesn't have file- system/certificate trusted store kind of things like in linux. When i look into Wireshark the client closing connection with Fatal,Bad certificate error. I tried all possible options which are suggested in different forums to solve this issue. Which haven't solved my problem. The solution i tried mentioned below.

By using below API to added only above Baltimore root certificate available in cert.c.

IoTHubDeviceClient_LL_SetOption(device_ll_handle, OPTION_TRUSTED_CERT, certificates);

it's not working for me because we don't have trusted store like linux.

ifdef SET_TRUSTED_CERT_IN_SAMPLES

    // Setting the Trusted Certificate.  This is only necessary on system with without
    // built in certificate stores.
        IoTHubDeviceClient_LL_SetOption(device_ll_handle, OPTION_TRUSTED_CERT, certificates);

endif // SET_TRUSTED_CERT_IN_SAMPLES

I need answers for two important questions.

1) Do i need to Add entire certificate string in cert.c (or) only first Baltimore root as CA root to my client.

2) Without trusted store, how client can tell to azure-cloud i have trusted root.

Any help would be appreciated.