Final answer:
The correct answer is 'God appears sporadically,' because throughout Genesis 12-50, the theme is consistent divine intervention, not sporadic appearances. This section of Genesis focuses on God's relationship with Abraham's family and the patriarchal narratives.
Step-by-step explanation:
Among the themes presented in Genesis chapters 12-50, the option 'God appears sporadically' does not align with the content, thus making it the correct answer to the question of which is NOT a key theme. The narratives from Genesis 12 to 50 cover the stories of the patriarchs Abraham, Isaac, and Jacob, showcasing continuous divine intervention rather than sporadic appearances.
These chapters typically emphasize A. God and Abraham's family, which revolves around God's covenant with Abraham and his descendants; B. patriarchal narratives, focusing on the stories and lineage of the patriarchs; and with the notion of C, the presence of the divine is indeed constant and significant as opposed to sporadic. Therefore, D. None of the above is not a correct option.