Ramos has 2 years remaining on his contract with Real Madrid,

Ramos has 2 years remaining on his contract with Real Madrid, ....................

1. but negotiations for a renewal have reached an impasse
2. while he will announce his decision to quit
3. although his relationship with the club is tense
4. notwithstanding his indecision about continuing with the club

Option (b) has incorrect tense usage, option (c) has incorrect usage of 'although' and option (d) does not make sense with 'notwithstanding.'