"The development that is undertaken by the government must obtain the support of the society."

Translation: Pembangunan yang dilakukan pemerintah harus mendapat dukungan dari masyarakat.

[donny309620]

"dari" can be optional here, eg., "Pembangunan yang dilakukan pemerintah harus mendapat dukungan masyarakat".

[marinsmam]

I agree with your opinion.

[Brian260733]

"Pembangunan bahwa dilakukan oleh pemerintah harus mendapat dukungan masyarakat." How is "bahwa" innapropriate here?

[kileli]

I think that "bahwa" is used for the "that" that's used with verbs like "say", "believe" etc. (I say that, I believe that). In this case, "that" is creating a relative clause. I would suspect that you could say "yang", but I will defer to a native speaker's opinion on if this is true!