Among the underlying components of the S&P 500 index, we saw noteworthy options trading volume today in Citigroup Inc (C), where a total of 93,712 contracts have traded so far, representing approximately 9.4 million underlying shares. That amounts to about 46.3% of C's average daily trading volume over the past month of 20.2 million shares. Especially high volume was seen for the $65 strike call option expiring February 19, 2021, with 11,223 contracts trading so far today, representing approximately 1.1 million underlying shares of C. Below is a chart showing C's trailing twelve month trading history, with the $65 strike highlighted in orange:

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Today's Most Active Call & Put Options of the S&P 500 »

ConocoPhillips (COP) options are showing a volume of 50,536 contracts thus far today. That number of contracts represents approximately 5.1 million underlying shares, working out to a sizeable 44.3% of COP's average daily trading volume over the past month, of 11.4 million shares. Especially high volume was seen for the $50 strike call option expiring February 19, 2021, with 22,429 contracts trading so far today, representing approximately 2.2 million underlying shares of COP. Below is a chart showing COP's trailing twelve month trading history, with the $50 strike highlighted in orange:

And Kansas City Southern (KSU) options are showing a volume of 2,915 contracts thus far today. That number of contracts represents approximately 291,500 underlying shares, working out to a sizeable 43.2% of KSU's average daily trading volume over the past month, of 674,990 shares. Particularly high volume was seen for the $217.50 strike put option expiring January 22, 2021, with 302 contracts trading so far today, representing approximately 30,200 underlying shares of KSU. Below is a chart showing KSU's trailing twelve month trading history, with the $217.50 strike highlighted in orange: