Grammar question below.What is the correct form? The origins of most sports is unknown/sports have been unknown/ sports are unknown/sports has been...

The basic grammar rule of the question is subject/ verb
agreement.  Essentially, we want to stress that the if the subject of a sentence is
plural, more than one, then the verb must reflect this.  For example, "The origins of
most sports are unknown."  In this sentence, the subject, "origins" is plural.  This
means that the verb has to be plural, so that the verb will be "are," to reflect the
plural of the state of being verb, "is."  I think that the sentence is seeking to
clearly establish the relationship of the past to the present day, and in doing so, I
find that a simple movement of the verb from the singular to the plural is all that is
needed.  The problem with the other options is that they are either grammatically
inaccurate or their verb tense is not consistent with the meaning of the sentence.  For
example, "The origins of most sports have been unknown" is reflecting an improper verb
tense, although its subject/ verb agreement is accurate.  It seems to me that we are
looking for a correct use of verb tense and correct subject/ verb agreement, which leads
me to the third option of the four featured.